Stephen Hawking’s Last Theories & Warnings About Future

Hawking's genius lied in bringing together several different but equally fundamental fields of physical theory: gravitation, cosmology, quantum theory, thermodynamics, and information theory.

In the last few years, he repeatedly warned about the threat of climate change, artificial intelligence, and hostile aliens. Here are some of his more recent theories and warnings:

1. Earth could turn into Venus

The British physicist warned Earth could turn into Venus if action to halt climate change was not taken immediately. He said Venus once had conditions similar to Earth with surface water, mild temperatures, and an appropriate atmosphere. The greenhouse effect burned the planet’s oceans and lands, and he believed something similar could happen to Earth if climate change continued unabated. Temperatures on Venus, at present, reach 250 degrees Celsius with powerful winds of 3000mph.

"Next time you meet a climate-change denier, tell them to take a trip to Venus; I will pay the fare," the physicist said.

Hawking was severely critical of US President Donald Trump’s decision to pull the United States out of the Paris climate change agreement, an international effort to reduce greenhouse gas emissions and was signed by 195 nations in 2015, He called it the most serious and wrong decision on climate change this world has seen.

2. The human race would have to colonize outer space in the next 200-500 years

The physicist repeatedly called for a new era of space exploration, in which nations unite towards a common goal. "It is clear we are entering a new space age. We are standing at the threshold of a new era. Human colonization and other planets are no longer science fiction, it can be science fact," he said.

The eminent scientist urged humanity to redouble its efforts in “seeking alternative planets for possible habitation.”

“We are running out of space on Earth, and we need to break through the technological limitations preventing us [from] living elsewhere in the universe,” Hawking noted.
This isn't the first time he made this dire warning, Earlier too, he had stressed, “I don’t think we will survive another 1,000 years without escaping beyond our fragile planet.”

3. Warns about the prospect of hostile aliens

Hawking warned against announcing our presence to any alien civilizations, especially to those more technologically advanced than humans.

“Our first contact from an advanced civilization could be equivalent to when Native Americans first encountered Christopher Columbus and things "didn't turn out so well", Hawking said in a film. Also performing a hypothetical flyby of Gliese 832c, a potentially habitable exoplanet located 16 light years away, Hawking noted: "One day we might receive a signal from a planet like Gliese 832c, but we should be wary of answering back."

"They will be vastly more powerful and may not see us as any more valuable than we see bacteria," Hawking warned.

He was also quoted as saying, "As I grow older I am more convinced than ever that we are not alone.” In the past too, Hawking had suggested that any civilization reading our messages could be billions of years ahead of humans.”

4. Warns Artificial Intelligence may replace humans

Hawking warned that artificial intelligence will reach a level where it can replicate itself and become a new form of life that will outperform humans. He went on to say that AI may even replace humans altogether without offering a timeline.

The emergence of artificial intelligence (AI) could be the "worst event in the history of our civilization" unless society finds a way to control its development, he emphasized.
At a conference in November 2017, he remarked, "computers can, in theory, emulate human intelligence, and exceed it."

At the same time, Hawking also talked up the potential of AI to help undo the damage done to the natural world, or eradicate poverty and disease, with every aspect of society being "transformed."

But he admitted the future was uncertain.

"Success in creating effective AI could be the biggest event in the history of our civilization. Or the worst. We just don't know. So we cannot know if we will be infinitely helped by AI, or ignored by it and side-lined, or conceivably destroyed by it," Hawking said during the speech.

"Unless we learn how to prepare for, and avoid the potential risks, AI could be the worst event in the history of our civilization. It brings dangers, like powerful autonomous weapons, or new ways for the few to oppress the many. It could bring great disruption to our economy."

In the past, he had ruled out the extinction of humankind because he believed humans would colonize other planets and stars. Perhaps the rapid pace of development of AI is likely to have forced him to rethink his thesis.

5. Humans need to leave the Earth to survive another million years

The physicist urged countries to send more astronauts to the Moon by 2020 and Mars by 2025 to 'elevate humanity', also suggesting that space agencies should aim to set up a lunar base within the next 30 years.

He believed there was no long-term future for our species staying on Earth. It would either be hit by an asteroid again or eventually engulfed by our own Sun. Traveling to distant worlds would "elevate humanity", he added.

He said human space travel was essential for the future of humanity because the Earth was under threat from climate change as well as diminishing natural resources. "I am convinced that humans need to leave Earth," said Hawking, adding that it was time to explore other solar systems as humanity is running out of space and the only places to go to are other worlds.

"If humanity is to continue for another million years, our future lies in boldly going where no one else has gone before," he said. "Spreading out may be the only thing that saves us from ourselves," he stressed.

6. There was nothing before the Big Bang

Earlier this month, explaining what happened prior to the existence of the universe, Hawking said, "There was nothing around before the Big, Big Bang.” His theory was based on the assumption that the universe has no boundaries. "The boundary condition of the universe ... is that it has no boundary," he said earlier this month on a show aired on the National Geographic channel.

The Big Bang theory holds that the universe in retrospective can shrink to the size of an extremely small "subatomic ball" known as the singularity. According to Hawking, the laws of physics and time cease to function inside that tiny particle of heat and energy. The ordinary real time as we know now shrinks infinitely as the universe becomes ever smaller but never reaches a definable starting point.

Hawking argued that before the Big Bang real ordinary time was replaced by imaginary time and was in a bent form. "It was always reaching closer to nothing but didn't become nothing," he noted. To help people better understand the abstract and confusing state, the physicist drew an analogy between the distorted time with ancient Greek philosopher Euclid's theory of space-time, a closed surface without end. "One can regard imaginary and real-time beginning at the South Pole.

There is nothing south of the South Pole, so there was nothing around before the Big Bang," Hawking said. "There was never a Big Bang that produced something from nothing. It just seemed that way from mankind's perspective," he added. He said that a lot of what we believe is derived from a human-centric perspective, which might limit the scope of human knowledge of the world.